Caklson



Sept. 6,1927.

w. T. POWELL AUTOMATIC TELEPHONE SYSTEM INVENTOR WNFRED T. POWELL.

BY A0 ATTORNEY Filed Nov. 3, 1922 m www mund? Sept. 6, 1921'.- 1,641,232b

y n W. T. POWELL AUTOMATIC TELEPHONE SYSTEM Filed Nov. s. 1922 e sheets-sheet 2 NVENTOR WINFRED T, POWELL BY ATTORNEY Sept. 6;-1927. W. T POWELL 1,641,232y

AUTOMATIC TELEPHONE SYSTEM Filed Nov. 3, 1922 6 Sheets-Sheet 3 COHMON NULTCONTACT RELAYS,

UN ITS REG\STR.

I n: l l

l fs l Si jl! 5 i 4 om l L 1u i K K O I 2 l )n i i' E l g n yINVENTOR LL I WINFREDTPOWELL b (f)- l 51 Il?. BY

ATTORNEY sept 6, 1927. 1,641,232

W. T. POWELL AUTOMATIC TELEPHONE SYSTM Filed Nov. 3, 1922 y 6 Sheets-Sheet 5 HHl HH HH NVENTOR wmFRED T. POWELL ATTORNEY Se t.

p 6 1927 w. T. POWELL AUTOMATIC TELEPHONE SYSTEM Filed Nov. s. 1922 e sheets-sheet 6 INVENTOR Y wmFRED n POWELL ATTORNEY 1 Patented iff* TED WINE-RED (Ti Bertin ternsyandf'ln'ore L systems en'iploying automat-,ie "f switches in completing f 'seine connection. L:v

One ofthe Applicatie i 4ortion of a, telephone `f nfeatures of "theg 4'presenti V' invention, -isf'tlie arre'ngeineiitby Whiehfthe y. talking oineetion extendsronlyffthrougli @non-nunneriil` switehes ot the non-'progresV u "Another featurev ofl this 'Vinginipulsesfy I -r L .Y au fWOtliereturesWill'apperfrom the del; `ist 'In the' drawings Figyl'represents two subscribe-rsf lines wi'thtle substatrons asso? Atliefconnection terminals )or springsof av u primary cross bar switchr One spring eomfY binationj jof f portion. ot* :this: cross-'bar eiated therewith;y `Wliielif lines terminateinf svitol appearsut' tlieleftof tlel dotted line.`

dotted line of this ligure there yis"reprel" sented'u portion of@y termin atingseeondary l cross-ber; switoh,gwlile below and -toi the right `of/:the K dottedgll there; 4appears' 5 fsoc'alled ,originariingul secondary `Cross-liar" y*talking connection. Atthe'bottom oflFigLu fthorenppers aportionofe"sol-calledfreg-fx n n l fcross-b-ar Withgxnafny ofits portions Vbroken utvsyffor `simplicity ini diselosureif 7j reprkes'entsftwo 'Viewsv of also-"called Vertical. 'rrossgrbar-y Figig' 18 represents the "detailed,

switch.. FigQ 4diii'grrninatieallysliows portion ot' a v"soi-,celledbridgeclrcult, with infr, 'undfbzttteryVfeedfrrangements of `aj' ister orossLljar @switch e which j serves f to; con- 'neet a register sender l'to "al v'selected bridge i Circuit. "Fig: 3 representsajregisterv sender'r 4which includesy zt tens'register and la; units"k register ofthe*rlaytyp 'als Well, 'as th '10 upper) right hfindf corner 'of this andf "jnzirtiall'y bounded loyftliedotted lines'there y n y barsyoooperate to,v actuate the' spring ooml binzitionsotlig. f8.. f

circuits for controlling the suine.""'t` ythe' tem. and which"*ooperterin 'the testing of l these lines. Figffi indieate's the" grd'upingv the @enter oi arrangementofthe line relaysof the sys-f tem, some of which areshofwn 1n the column' of this-figurethereA appears' the so-ealled" vertical, magnets, While wat, `the bottom ot armature springfengg ,theyangul ARLsQu/Tnrniifoun flvniiirecrunriis TCOMrANY, on ',RooIIEsTEn, yYonx, 1.) "Y .ACOBPOBMION'QFfNEWCQRKf e 'Y f 5 findieate's' ytlne `arrangernent/of 4the `ilstrious lasint' Fini. diive not-*been showin connecussoiutedfvitlifin even; link Circuit; from 5 wliielr it; should Aloe understood tht areluy such as 136` associated`k Withj'tlie selected bridge Circuiti cooperates with si.k relay inj 'one such vets altlund122, are operated depending l on Whetherthelwanted line'is oddoreven to' etuatfethe yertiealmagnet ,or horiion- ""i/Figuresv 6,67, .8,

'build' fuir ,Porti/01?" Views Vof a," set y of interconnecting L springs" of the `cross-loer Vswitch,wjvhile Fig, 9 4discloses u' portion of "aJl10r1Zontal`bZr ande portion @empty-step ,silgtergswiteu @bien functions t0l design' un idlelink ci'r'f'niitfor use d i'ntotheremainderfoftlie sjfsteinibutloy,` I kreference "toFiguresjjlifand f2 'it Will be Y readilyunderstood tliatone of therotvslof. relays ,suoli releyfl'f isjassociete'd with ,ah Y bridgeA circuit;` :While :onefoftherelays j of anotlierro'wsuelifas150yisi'assdoiitedwith n odd" link`eirouitjfandzfone.of* the relays 1 ,oija'notherrow such asis' designfited'2122'a is k0f thekt Vertical bali '10@ L indicate Y how 'these y lllie dSfgn yof the `Windings Ot they `relay 91 springfQ which tney `loe e'onsidered'es the ai* l:

e' ,other tesis ings .onerof'wliioli is 'high'. gandtlie otlie'rjllow l `resis yence, I airefj'energlzedf lnserles. The 105 .spring the armature is fully attracted, so that uthe kcondition of all the contact sets is contrary to that shown in the figure.

i vThe system.

groups of 30 lines, which are still further sub-divided into .sub-groups Vcontaining a socalled odd line and an even line, and when taken togetherl are referred to as a pair.

These lines through the cooper-ation of the mentioned primary cross-bar switch have accessto twenty-.eight link circuits which are arranged into fourteen pairs. Then one or more of a pair of telephone lines initiates a call, this pairof linesisextended through the primary cross-b arswitch to an .allotted pair of `idle link circuits which have Abeen assigned for use by the allotter switch of Figf4. Each vof these link circuits is then independently ext/endedv ythrough an originating secondary cross-.bar switch to `any allotted one of ten bridge circuits and these ten bridge circuits are .connectable through the operation .of a register .cross-bar .switch to any allotted one of live register senders. By reference to Figs. 1 and 4 it will be seen kthat forty-tive relays such as ,51 are provided for i 90 telephone lines. VOnly twenty-three of these line relays have been shown, butthe numbers appearing `in the' column at the extreme left of Fig.` 4 .indicate how the ,armatures and contacts of the remaining relays are connected into 4the system. While only .twenty-one of the vertical magnets of the primary cross-,bar switch are shown, it will be .understood that inav comV plete system there are forty-two of such magnets which Vare connected to the terminals of the y1allotter in vthe manner indicated by the numbers adjacent each of the terminals which refer to the remaining vertical magnets. All of the horizontal mag- .netsl of the primary cross-bar vswitch are shown. In explaining why there are fortytwo vertical magnets and only fifteen horizontal magnets it should be stated, that since there are Vthree groups of telephone lines, each of the vhorizontal magnets isl common to a line in each of the three groups. This isindicated by showing thatvthenumber 1 horizontal magnet is connected to the armature of the :ttl line lrelay designated 51 and to the armatures of line relays 16 and #31. Also each ,link circuit appears before each of the three groups of telephone lines, and since fourteen link circuits are provided, it is necessary to `provide fortytwo vertical bars, which is the product of Iourteen times three.

In the secondary cross-bar switch, the

number of horizontalmagnets is fourteen because there are fourteen link circuits, while the number of vertical magnets of the secondary originating cross-bar switch is twenty, since the fourteen link circuits are connectable to ten bridge circuits. The showing of the vertical magnets, horizontal magnets, secondary line relays and the seconda-ry allotter has not been made, but it will be understood that except for the number of the various relays and magnets it is similar to the grouping of these elements. as shown in Fig. 4. It will fbe understood that the number of secondary lline relays is twenty-eight, and each of the fourteen horizontal magnets is connected to the armatures of two secondary line relays.

In this instance the secondary allotter is provided with only ythree brushes instead of four as in the case of the primary allotter, and thernumber lof terminals in the allotter bank is ten instead of fourteen as in the case of the primary allotter.

In the controlling circuits of the register cross-bar switch there are ten relays such as that designated 81 in Fig. 2, one of these relays being associated with each bridge circuit. In this cross-bar switch there are five horizontal magnets and ten vertical mag-y nets. .The allotter associated therewith.. while it is controlled in a manner similar to the allotter of F ig. 4 is provided with only three sets of brushes, which engage five sets or terminals.

ln Fig. there are shown the vertical and horizontal magnets of a terminating crossbar switch. In this instance there is no need for an allotter switch, since it is necessary to connect a bridge circuit selected by the .calling line to the particular lin-k circuit that has 4been seized by the called line. It will be seen that there are twenty `vertical magnets such as l152 and fourteen horizontal magnets such as 153. The seizure of a bridge circuit such `as that at Fig. 2 effects the energization of the` relay such as 13G .and the testing and Yextension of the called line to a link circuit .effects the energization of a relay such as 122. The operation of relays 136 and 122 causes the .operation of vertical magnet 152. The energizat-ion of relay 122 causes the operation .of horizontal magnet 153. By referring to Figs. l and :2 it will be understood how the relays 122, 136. and 150 of Fig. v5 areconnected in the various links and bridge circuits of the system.

The switch structure.

lill

"10 y a 'ro l frame andk sliowniin" deta-iljn fFig'.: 8. These .y '5 lthey 'are arrangedgto heioperated' 'automati-V callyinsteadof ymanually. v Ahar 112i isi ar'- ranged 'for :horizontal motion .either 'towards c p ftheright-or4 tojiardsthefletfandactuates fthe motoiispringfs lofthey'arious sets. While;r y n"y't'13:monntedthereon'isengaged by ii'regular Shapedhspring or latch 1111 to y holdthe'har and its actuated-springs in the K lheen niovedf t" timeqthat thehar v12 n catch tends to" hold ythe 'line and link?. ter yminals in'engagementuntilr the time thatlfa f position to lwhich it ha 5 taneously iactuates "twofsets "of kterminal IN1/springs as shown, inthey righthand `View of Y f :'Iflie mechanis'nffor'L operating the i fi/arionjshais 12 includes a plnralityof/Ver-'f yide'd 'with 'a crank arm l15 20' vtical hars? 1&- x y* I I and spaced extensions or 'lugs 16, all-mounteed for rotation in 'the' frame:1Qf` The rota-V` y tion of the' har4 141r visr 'electedhy expansive Y, air 'chambersi*'17v and18 Acomrn'only@known 25 jas sylpho'ns, operated'byfasupply of coin-iv pressed air appliedfthroughfanair supplyv 4pipey '179. VThe' magnet 2O yoperaftes afvalve to .a supplyjof air intof airchamher' 1'?v While ai-niagnet 22actuates Valve 23 "liuto allow'airfto passintothe 'expansive air chamber 18 ltflwill ofcourse he under-y stood that the A,number of yertical yloars such "15,114 Willjdepend upon the `n'umloer `of lines 1lm ivhich terminate each'sivitch, A plural-4 i 3'7"; ity ofhoriaciital hars 24 are lilreysiise 1n`onnt-- ed lfor rotation/inthe'frame 10.V k*Each bar j Lfihas offset portions'tofpreyentj-its inter# tering lwith the *operationy ofy the,r sets kof tery .fuminal .springs and is" also, provided (with,k mfflugslsho-Wnindetailun F 'and a` `r`r`crank port-1on1 notA shown. v` 'The 'expansive ainch'ainhcr t2.6 lis" mounted to engage the crank' portionfflor rotating the horizontal "15 VWard ybetween theextensionslG and` 33 as i501 vtif'ianglil openings such as, 30', "which ,fu'ncf tion r`to restore loars 12 to'ynormal position,V "Each" opening in har; 29" receives a roller such as 31 carried fon the end ofthar 12' "soy i that when thel release har 293s elevated the D, roller 31 enL jBlLtfojnioyethe harj12 `Vithits motor springs y 'intoneutral'position"asshown"inFig; 6."

t yofi three .y release vhars 29 fis actuatedy hy the' expansive air chaniherBZ loutth'is isdue toil'le coupling of lines *and* trunks in `the crossfh'ar 'su-itchAv` y ln the I 4 apair `oil-,d

11 ith'er @tesiight or "vleftmovement simul-- es;k the sides 4*of the" opening KK aeration 'of the `v prin'aary switch le ylink circuits v1s normally allot-1y e ted for. use, a Will hefdescriloed'sxthfat:on

275 operates a valve 28twhich turnfadmits then` either magnet' 20 or`22 s'op'e'rated.

ity 'he vassumed.that the ymagnet 20'lis' operatedl to' actnate-,itsValve 21,-to` releasey air into the expansive airchamloerl,which rotates the vertical har 14 towardsthe left@ The lng 25 communicates vthiefm'otion" through extensonsy to rvmove the harg12 i towards the leftjuntil thefro-ller v13y engages.'

the left hand 'catch of spring le. This i sofa r release magnetsuch asl 34 operates a *Valvefy` The, structurefof the primary secondary cross-bar switches is. thek'wsame except f n f that Ain the primary cross-har "switch the number of spring combinations `rlplfas Wellv asn the number of' release hars. isfv greater ftoactuate the expansive airy chamber 321- Thisr elevates they set of three release hars `29to^1nove tliehar 12 and'litsfmotorspringsc to normal positonf f inthe primary crossharwswitch ,they spring 1 combinations, such as 11 com/prise four setsv or" line andr trunk terminals and `rthe release hars yare arranged in gronpsotl three;` eac-h single expansiye chainherrsuch as 32.

f `grol'ip'beingy actuated by thefoperation of a 'isf'known as anfodd spring combination or an even springfcombination. ,Alsoin the r secondarycross-har switchesthe release hars are arranged in groupsof'twoye'ach group f hei'n'go'perated by a' slngleexpansive chain# u Aher..` c, y v n i The register cross-har `issimilar in strucf lturefand operation to* the primary and secondary cross-har switches.`

,` Operation of" thefsy'scm.:

'nis `,believed that @reinvention ,wartest n lhe* understood by descrhingthe niethodmf* y.

esta-hlishingfatelephone connection yfrom a y substation such as Arto' substation herein designated `Bfand to which the designation #1() is assigned.

When the subscriber atk removesfhis re- `ceiver from its vswitch hook af circuit isclosed from grounded battery, armature andy back j contact of relay 50,. baclrcontact and continuity spring of relay 51, right-.hand Windf ingy of this relay; contact 53 n and armature ot' cut-ori?v relay '52, oVer the lower side' of the jcallingline, through the vsubstation vcircuits in series,` over the yupper-sdeof. the calling line, armature kand,contactfjtof'relay to i i l groundjf The rel'ayl, yoperates-y andifcloses-l In the secondary cross-har'switchesfthefWU* {springfcombnations such as 11 include` rthe following circuits: On the operation oit' the relay 51. a horizontal bar magnet such as the lirst ot the series in Fig. 4, is Aenergized from grounded battery, winding ot this magnet, armature and contact 56 of re-lay 51 kand thence to ground. The Vertical bar magnet such as the first ot the series in Fig. f

t is operated from grounded battery. front contact and armature ot the operated horizontal magnet, armature and back contact of the rela)v 192. brush 19t in its lirst position through the vertical magnet vto the con- '7' armature of relay 65 to ground.

tact and armature ot relay 51 and thence to ground. The operation of the horizontal and a vertical magnet operates the vertical bar and a horizontal bar ot the cross-bar switch to close two sets ot contacts in the manner already described. As soon as the set of Contact springs 5S is closed the operating circuit ot cut-ott relay 52 is completedL causing it t-o attract its varmai'urcs and thereby disconnect a pair oi' lines such as #10 and #19 `trom the line relay 51. At this tlme the calling line is extended through contacts 59 and 60 to that portion ot the secondary cross-bar switch that is assigned to odd originating telephone lines. Alsov the closure oit' the set oit springs 57 extends the telephone line Yfrom substation B through springs 61 and 62 to that portion ot the secondary crossbar switch that is assigned to even originating telephone lines.

It should be mentioned at this point that the calling line #19 and the called line #10 are extended by the closure ot the single set of springs 57 merely because these two lines happen to be paired together. Also it one of aA pair of lines originates a call both of these lines are simultaneouslyextended to a pair of idle trunks. Then the calling line is extended through contacts 59 and 60 a circuit is completed for the -relay 63 'from grounded battery, winding oit' this relay, contact 6i and armature ot secondary cutoff relay 65, conductor 66. tirough contact springs and the calling line in series. contact springs 59, conductor 67, Contact 68 and The relay 63 on operating closes its contacts 69 and 70 which complete operating circuits for theV vert-ical and horizontal magnets associated' with the contacts 71. 72, and 73. `These magnets operate and close thesey contacts to turther extend the calling` lines over conductors 66 and 67 to the conductors 711 and -ot the secondary trunk leading tothe originating end ot'aso-called bridge circuit. The closure of contacts 7 Biconipletes an Aenergizing circuit for relays 146 and 65. Relay ythe relay 192 vis energized from grounded battery. relay 192, test brush 191,: and the mentioned grounded test contact. l.lilith relay 192 energized, an operating circuit is closed for motor magnet 193 which causes it to advance the allotter brushes 191, 191i, 195, and 196 until test brush 191 locates an idle pair of link circuits.

The extension ot a calling line to conductors 74 and 75 completes a circuit through the lett hand winding ot relay 76 to ground, and through Contact springs 77, conductor 78 and right hand winding ot relay 76 to grounded battery. Relay 76 energizes and completes a circuit from ground, conductor 79, armature and back contact ot relay S9, winding of relay 81 to grounded battery. Relay 81 closes its contacts 82 and 83 whereby the vertical and horizontal magnets of a so-called register cross-bar switch operate to connectl an allotted register sender to 'the bridge circuit. Simultaneously with. the enerfvization of relay 81, slow releasing relay 84 is actuated from grounded battery, over conductor 79 to ground at the i'ront contact and armature oi relay 76 and when the springs 85 ot' the register cross bar switch are closed, relay 80 is operated from grounded battery, its winding, inner front contact and armature ot relay 84, contact springs S5 to ground. On the closure otcontacts 86 ot the register cross-bar switch an impulsccircuit is extended trom grounded battery` winding of the impulse relay 87 ot Fig. 3, conductor 8S, contact springs 86, over conductor 75 to the lower' side ot the calling line and through the substation circuits. over the upper si de ot the calling line. conductor 74:, left hand winding of relay 76 to ground. The impulse relay is thus energized and etects the operation of the slow releasing relay .88 from `rounded battery, resistance, winding ot this relay, continuity spring and armature ot relay 87 to ground. The operation ot relay 88 in turn effects the actuation of the slow releasing relay 89 which relay at its uppermost armature and iront contact applies a busy condition to the contacts assigned to this register sender at the sender allotter. r1`he relay SS also effects the energization of slow releasing relay 112. rlhe circuits are now in condition to receive directive impulses corresponding` to the designation of a called line which in the case assumed is :tt-10.

The subscriber at A thereupon operates his dial sender to transmit one impulse which effects the momentary release of the impulse relay 87. This operates changeover relay 90 in a circuit from grounded batter,f l, Wind.-

ofi-clay v,970, nnerifront contactv` and ar-K-yl niaturefotq relay 88, bacl; contact andcontinir--" ityfspring otl relay 87 toi ground. Also, ani'ul amasar] ftiple operating circuit is clo'sedlffor the v'countingr-clay 91 :of yther tens relayregi'ster. Thisv n,circuit istraceablefrom rgrounded battery,

` throughtlie low and high resistance Windings ot relay 91 back yContact 92 andarmature of `this "relay," back Contact and armature of switching relay 93 togroundjatthe back con; tactandcontinuityspringfof relay 87 as pref v'iously describedlv l' The relay 91 is so'd'esigned the' impulsel relay, conductor, left hand that it attracts vonly' 'its armature f9l whenv` both of itsy Windingsjare' includedin series, Withftheresult that when impulse relay 87 `is ,again operated vra circuit' yis closedvr from ground, continuity spring and armature of back` 'contactA continuity y spring and armature of Arelay 91,,leftfhandwiyinding of this. relay wto grounded battery'. V rrtthis time relay 91 attracts bothj'of its armaturesand thereby extends the impulse circuitto the #2 count! -f ing` relay ofthetens register. l l, f f v iDuringthetiinethat the changes-over reaV lay 90 isgoperated, While' the tens-.serieswof impulses beingltransmitted, .a circui'tf is, closed r ,from grounded battery,y 'throughl the high and lowA rresistancewindings of relay 93, its outer backv contact and armature, con-kv tinuity'vspring.and armature of :relayv 90 to ground. The -relayi93 vis similar in .structure Ato' the relay Vshown, in'Fig. rlOnso that the circuitx just described is elfective' only .to bring the inner armature 941 of this relay into engagementjwith its` continuity "springI with# A outo'pening any of the/back'contacts; 'At

lthe close of the tensseries 'of impulses, ho`W-' ever, the changeover relay deenergizes vand thereby rcompletesa circuit `from ground, i v its continuity spring and backcontac-t, backcontact,y continuity spring and 1 armature Aof y relay v93,v its 'lowv resistance Windingto grounded battery. ''l`he relay 9,3' is completelyenergi'zed vin this last circuitand attracts. its armatures andr through its inner armature,- continuityspring [and "front contact closes f aA locking 'y circuit for itself throyighits ,left hand y`,Winding andy the holding. conductor- 97 to ground,Y through the leftvliand front' Contact and armature of relay 88.l yThe oper,- lation ofy relay 93, alsoremoves the tensregis` teryrelaysr from thecontrol of the impulse"V `relay 87 and directiyelyy connects thecontro'l vot this lasty relayvtotlie group kof lrelays of f the units register.'` The y register sender'is A. nonT in condition to'` receive the units vi-iiipulse ol the Wanted number rwhichfinthey case fasrsinned Was fOQ Ther callingsubscriber thereupon proceeds tol send vten impulses.

'ot these impulses,impulse'relay'87 retracts and attracts vits armature.y

spring @aanname/ier Tanyae7 regroupe r IAr circuit in multi ple of that` just f described y Y' `is also`completed` froinjg'round, 'continuity [spring 'and back Contactof`r'elayj87, inner*` rain'iature and front contactof "relay 88,leftfr hand armature' and front' Contact ofrelay 9,3,` baclrfontactj and armature '99;y of relay y'98, y,through.both.windingsfin series ofit'his relay y to grounded battery. Relay4` 98 is only*y par@ tiall'y` operated Vin this i circuit"J to bring its armaturerlOO into engagei'nent with itscom tinuity spring Without interrupting itsfbafck" contact. When, lioxyeyerfthe impulse relay. again attracts its armature. completes a circuiti; from ground its) 'continutyj spring and armature, outer back Contact, continuity ten relays vare operated. Y

- 4At l'the tiinewhenfthe' change-over:relay` attractedy its armature v in response to the 'first units impulse, a circuit vfor thel switching continuity spring an'd armature of relay 90,

outermostlarmaturefand lirontcontact of relay 93, throughfboth windingsin series kof vrelay 102f`wa's closed'd'from "ground, at the luis 1O'2'ispartially operated in this 'ci'rcuitto bringits armature 103 into engagement VIwithr itscontinuity spring.4 1.At the close of the units series of impulses when rthe ychangeover fie'lay`90'is again deenergized; the relay i102 is l fully operated in a circuit noiv'closed from grounded battery, through `its low resistance Winding, arainture 103, its :continuityspring and back contact, vback contact and continu yity, spring otrelayfto ground.

lll):-

` At thecloseoftliis last series. kof impulses,

ii'no' other one of the register senders' is test- `ing tor ai'` called line, the relay 104i eects the test of theft-vanted line #10. `There is [a relay similar; 1:61104' at'ea'ch of the five register senders of" they system and the `circuits through the contacts of these'xfrelays vare so yarranged thatit any one of the relays f Vis operated, no othery relayf corresponding rthereto Ycan be` ksimultaneously `s actuated.rk

Thisv is shown in kapplicantsfcopending 'ap-f plicationk Serial `it583,113,` filed August' 21,'

V1922;issued as yPatent No. 1,531,219, Mar.v 24;, I

1925. 'Since itfiyas' assumed ythat no ,other register' sender is ready to test a called line:k at thistime,r a circuit is closed from ground at thelast switching relay similartoflOe in series, through the back contact 105 and the continuity spring ot relay 104, through bothwindings in series ot' this relay, right hand armature and front Contact of relay 102, through armatures 106, 107,108 and 109 ot the actuated units register relays, conductor 110 and winding of `the #5, multi-contact test relay 111 to grounded battery. 1t will be understood that the group of common inultif contact relays controls the test circuits of all of the telephone lines in the same manner as relay 111- controls the test circuit of the present called line.

Relays 104 and 111` are operated in this circuit and relay 111 attracts its armatures to close break-points in the test circuits of this group of lines. The relay 104 interrupts the operating circuit of the slow'releasing` relayl 112 and the first mentioned relay at its right hand armature and front contact closes a test circuit from ground at the right hand armature and front contact of relay 88, right hand armature, front contact of relay 104, continuity spring and armature of relay 112, conductor 113, winding of slow releasing relay 114, armature 115 and. backcontact of'relay 96, conductor 116, contacts 117 ofinulti-contaet relay 111. Conductor 118, and it the cut-off relay or the pair of lines in which the called line is included is not operated, this circuit is eX- tended through the left hand winding of a relay similar to 51, its continuity spring and back contact, back contact and armature of a relay similar to 50 to grounded battery. The relay 51 operates in themanner,already described to cause the primary cross-bar switch to extend the called line to an idle primary trunk. Since it has been assumed,

however, that thev called line is paired withv the calling line, the primary cross-bar switch is already operatedfand the called line is eX- tended to an idle primary trunk so that the test circuit including conductor 118 instead of being completed through the line relay 51 is extended through contacts 119 and con` ductor 120, outermost back contact and armature of relay 121,A winding ot relay 122,

conductor 123, through the outermost lettV hand continuity contacts and armatures of all the operated units register relays in series, conductor 124, lett hand front contact and armature of relay 104, resistance, to grounded battery. Relay 122 is operated in this circuit and since it is a secondary line relay associated with an even terminating position of the secondary cross-bar switch it causes the vertical and horizontal relays to operate the set of springs generally designated 125 to connect the called line to the terminating end of the bridge circuit of Fig. 2 to which ithas been assumed the calling line has been connected. l

When the relay 84 is operated, it closes an acuating circuit for the ringing relay 126 from grounded battery resistance, winding or' this relay, conductor 12.7, right hand front contact and armature o't` relay 84 to ground. jWhen, therefore, the called line and substation B is extended through the primary and secondary cross-bar switches to conductors 128 and 129 by the operation of the even cross-bar switch springs 125, ringing current is supplied from the generator through the winding ot the trip relay 131, front contact and right hand armature ot relay 126, over conductor 129 to the substation at B and the signal thereon, over the upper side of the extended connection, over conductor 128, lett hand front contact and armature ot' relay 126 to ground over conductor 12'?. The called party at substation B 'signalled in this manner and when heY responds by removing his receiver from its switch hook, trip relay 131 receives suicient current to operate and attracts its armatures. At its left hand armature and tront contact, it short circuits the ringing relay 126 causing this relay to deenergize, after which the. trip relay 131 is locked operated in a circuit from grounded battery, right hand winding of the trip relay, yits front Contact and armature, lett.. hand back contact and armature ot' ringing relay 126y to ground at the iront contact and right hand armature oi relay S4.

It will b'e noted that battery feed relay 132 is operated as soon as the ringing relay deene'rgizes and closes its armature and bachr contact so that talking battery is supplied to the called party through the windings of relay 132', while talking battery is supplied to the calling party through the windings of relay 76.

It should be notedthat as soon as the test ot the called line is made, the register sender is released. This is brought out in the 'tollowing manner. The circuit of relay 114, which it will be recalled is included in the test circuit of the wanted line, is interrupted by the release of relay 112, and when relay 114deenergizes it short circuits and releases the holding relay 8S which has been holding the register sender during its operation. This short circuit is completed 'trom grounded battery, resistance, front contact and are mature ot' relay 89, uppermost back contact and armature of relay 114, lowermost back Contact and armature of relay 112 to ground. Then relay 88 isfthus deenergized, it also opens the circuit of slow releasing relay 89, which has been maintaining a busy potential on the test'terminal of the sender allotter. However, before relay 89 deenergizes a circuit is completed from ground, left hand armature and back Contact of relay 88, inner armature and front contact of relay 89 and winding of the release magnet 134 to grounded battery, which operates magnet 181i in j afinanner already*describedwtorestore-1y c, theoperatedcontactfspringsof thefregisterw y t y *143, arn'iatureand-front contact'of relay lele, conductor '145 ,'y winding of the 'release inagnet (3.146 f of'the terminating -crossbar"switch cross-bar kswitch i to p normalvposition;` E;

Let` it now be assu1ned that ythe wanted; i lineV is` busy, at the time when the testv thereof-j (is Inade, resultf'of which* conditionifthe' y test circuitincluding 'conductor 118 is'open either at 'the'"armature'andback contactlof' the calling `substation.

` arn'iature and ifrontcontacti of ,relayy 14st),` armature f and. ,back "acon'tact'f of relayf 65,nz

.i vated contactant the primarycrosslbarswitchiv cut-olf relay 52 ,or at the 4arr'natureandbaci;`

contact of f relay 121`1sothat relay 114? "not operated.` Instead of this, the test relayfl is energized .,froin groundedKV battery, its `v winding, continuity .springend back contact,

armature and back Contact., of* relay f -186,`

'contact y'springs 137, yconductor 138,finner back contactl and 'armatureof relay '114,'vr conductor 131,innermost-r back contact" and `armature of relay 112,' `front contacts and @armatures of relaysf'lOljandy88'ito` ground;

Tlief'test relay 13,5 isfenergized jin' vthis circuit and at its continuit s rino` and arma-y f l ture closesv a: looking. circuitfor vitself to ground at the right 'handffrontf contact and armature of 'rela}'ff80,V which' circuit is held` complete` until the calling party rele/ases; With relay 135?operatedfjthe [busy tone curr`rent is transmitted tothecalling'stationf from the source BZl through the right hand armatureand front contactvof relay 135 and over the connection. already 'established f 'At the terniinationof the connection lwhen the calling subscriber replaces liisreceiyer` on its switolhoolr, thefb'attery feed relay "E6 releases to: effect 'the deene'rgiization; of vrelays 8() ande. It willbe understood, however,` that inl ythe "interval, between rthe `release "of 1 relays 80 andy a" circuit vis completed through the release Inagnet`139of the orige-V nating crosslbar switch of Fig. 1 causing this mag-netto operate and restore the operated originating springs of the secondary crossbar switch invth'e manner already described.l vThe "release of' 'the originatingy `Cross-bar switch openstlie contacts 73,"w`, hich ininiedi'' ately causes the ldeen'ergiration 'ofiel'ay 65' and shortly atterwardscauses the'deenergi-.I/ zation of slowkreleasing relay llOQn the interval between the: deenergization ofthese.l

two" relays acircuit is closed from ground,

right"` handl armature4 and back Contact'v of relay 121, windingfof the release magnet [142"` y to lgroundsd battery.` VThe release magnet4 lflQfis thus operated and :restores the'oper to theirnorrnal position;

leihen Ythe called fsubscriber replaces his receiver on," its switch hook, the' 'battery1 Vfeed relay 132 deenergizes causing' thedeenergin, zation ofthe slowjreleasing relay 1.43, and

the release of ethisv lastnarned relayffshortly i afterwards. effects'theI deenergizjation of re#` lay 144i. lny the interval betweenthe release of these" twov fi'elays, ak circuit-is closed from i groundgfarniature-andlfbaclr` Contact ori relay I which effects thefreleasevof the v'operatingf plurality yottelephone lines, a plurality v of f linkj circuits,fa fcrosv's4bar fswitch, contacts of-fsaidtelephone lines andvcontacts of sai'dl link .circuitsin-said cross-bar switch, means operative on the 'initiation of a call on one of saidlines'ffforfclosing a Contact of said ing linefor closing a contact" of the" called lineffanda contact of a second link circuit,

andineans `for interconnectingsaidv selected 2; In i automatic telephone system, a pluralitf fofftelephone lines arranged in lines of, apair forlconnecting 'said pair of telephone ylines to,` af pair oi' idle` trunks,

means controlled over *sa-id" calling telephone rline for connecting the Vcalled telephone line i to an idle trunk,""'and means for*intercon-,fI

necting'tliev trunks to which the-calling and n called telephone lines'are connected.

,3. In an automatic telephone system, a

, plurality"t of :telephone lines, a plurality" of link'circuitsfa@plurality of bridge circuits,

nieanswincluding a priniarylcross-bar switch for' interconnecting a calling telephone line andan idle-link circuit,- a secondaryl crossf bar" switch for interconnecting; a selected' ylink circuit' and van'idlef bridge circuit, a

pluralityofregister senders, ineans including anothercross-bar switch io'rconnectingv t Y thek selected bridgefcircuit to an idleregister` sender, ineans''cont'rolled over' the callingv `-telephoneline k"fordirectively operating the f selected register' senderrv to store the ldesignation of' the y called telephonef'line, ineans con'- trolled by said register Vsender for causingy 'saidfpriinarycross-bar switch to extend thel called telephone line to another linlr circuit;Y an ladditio'nal secondary cross barr switch,vr

ineansfperatiye"on Athe seizure-oi" said sec? ond'liiik circuit 'for operatingsaid lastinem Ationed"cross-fbai" swi'tch toconnect said li'nl circuit l"tol the previously selected bridge circuit, and means responsiveto"'s'aicl1conneC f `tionfor releasing"'s`ai,d 'register sender,i 'I j l 4. In anautoinatic vtelephone systein`,ax`

ypluralityoftelephonelinesg a plurality of? bridgecircuits, a pluralityu of non-numerical switchingfv'nieans" for extending said telek n Llo ranged to be variably operated to store the designation of a called telephone line, and means controlled by the operation of one of saidregister senders for. causing said nonnumeri-cal switching means to extend the called telephone line tothe selected bridge circuit.

5. In an automatic telephone system, a

plurality of telephone lines, a plurality of bridge circuits, a plurality of non-numerical switches for extending .said telephone lines to said bridge circuits yto complete telephonic connections, means responsive .to the initiation of a call on one of said telephone lines for causing said non-numerical switching means to extend said telephone line to an idle bridge circuit, a plurality of register senderseach including a plurality of groups of counting relays arranged to be lvariably operated to store the designation of a called telephone line, means controlled by the opV eration of one ot said register Senders for causing said non-numerical switching means to extend the called teleph-oneline to the selected bridge circuit, and means responsive to the interconnection of .said calling and called telephone linesv for releasing said operated register sender.

6. ln an automatic telephone system, a plurality of telephone lines, a plurality of bridge circuits, non-numerical switching' means for interconnecting said telephone lines and said bridge circuits, means responsive to the initiation ot acall on one of said telephone lines for operating said nonnumerical switching means to extend the same to an idle bridge circuit, a plurality of register' senders each including a plurality of groups of counting relays arranged to be variably operated to designate a called telephone line, the relays of each group Vbeing operated in succession, a test circuit lfor each of said telephone lines by which the operation ot' said non-numerical switching means is initiated to extend the called telephone line to a selected bridge circuit, means including` said groups of relays for completing the test circuit of the called telephone line, and means `responsive to the interconnection of the calling telephone line and called telephone line ttor releasing the operated register sender.

7. ln an automatic` telephone system, a plurality of telephone lines, a pluralityof bridge circuits, means including non-numerical switching means Jfor extending said telephone lines to said bridge circuits, a` plurality of register senders each including groups `of relays arranged to be yariably operated in accordance with one or more digits of the designation ot t-lie'called teleu phone line, means responsive to the initiation of a call on one of said telephone lines for causing said non-numerical switching means to extend the same to an idle bridge c'rcuit, means responsive to said extension for associating an idle register sender with the selected bridge circuit, means controlled over said calling telephone line 'for variably operating said groups of relays, a test circuit for each Atelephone line, a group oi' multi-contact relays, means ,including the groups of relays of the associated register sender and said multi-contact relays for completing` the test circuit ol the called telephone line, means responsive to the completion of said test circuit for causing said non-numerical switching means to extend the called telephone line to the selected bridge circuit, means for thereupon signale ing the called telephone line, means effective on the response oit the called subscriber for disabling said signaling means, and means for eliiect'ng the release of said register sender.

S. ln a systemv of the class described, a series of relays arranged to be ope ated in succession, each relay being operated in two distinct stages and subsequently released, and means Yfor operating said relays.

9.111 a system ol' the class described, means for generating a series ot impulses, and a series of relays controlled by said series of impulses, each relay being operated in two distinct stages in response to an impulse and being subsequently released.

l0. In a system of the class described, two serles ot' relays, the relays oi each series being arranged to be operated in succession, each relay being operated in two distinct stages, common governing means for said series of relays, and means for transferring the control of said governing means from one series of relays to the other series.

ll. In asystem of the class described, two series ot relays, the relays oi` each series being arranged to be operated .in succession, each relay being operated in two distinct stages and subsequently released and common governing means including switching relay operating in two distinct stages.

12. In a system of theclass described, an impulse relay arranged to be energized and deenergized in response to directive impulses from a distant point, and a series oi? relays arranged to be operated in two distinct stages in succession, each relay being operated one stage in response to the deenergization of said impulse relay and prior to its release being operated another stage in response to the subsequent energization of said impulse relay.

circuit, l n p switching means for vextending the selected l 13. In a vsystem of the class described, means for generating a series of impulses, and a series of relays for counting said series v4of impulses, cach relayjbeingprovid-ed with two sets ot contacts operated at different operated at the'beginiiing of each'irnpulse ofthe series'and thel other of said sets of contacts being operated at'the close-ofveach,

impulse of the series. i y

14. In a system: of the lclass described,

means for generating ak series `of impulses,-

and ya seriesfoi: relays toircountng said series ot impulses, each relay having a high resistT ance winding and ay low resistance winding,

the windings ofceach relay functioning to loperate itin two distinct' stages in responsel k.to each impulse l5, In a systeinot the classdescribed', means for'generating a series of impulses,

impulses, each relay being provided with two windings and two sets of contacts, means operating in response to any impulsefor energizing both of said windings to closeone'of its setsof contacts, and" other kvmeans controlled in response to said impulse for energizing one ofs'aid windings only to close bothot said .sets otcontacts. s

15. In an automatic telephone system, a plurality-'of telephone lines, a pluralityof llink circuits, a kcross-bar switch, contacts of said telephone lines and contacts ot'saidy link circuits in said cross-bar switch, means operative onthe initiation of a call on one f of said lines for ,closing contactso'f said'line and contacts of an idle link circuit, a bridge means s including nonnumerical link circuit lto said bridge circuit, means `directively controlled overrthe calling line i for closing contacts of the vcalledjlineand contacts or' asec'ond linkcircuit, and meansv I for interconnectingsaidy lastv mentioned link circuit and said bridge circuit. l

17. In an automatic telephone system, a

plurality ot telephone lines "arranged iny pairs, a 'plurality of trunks, a cross-bar switch having contacts by` which said telephone lines Vand trunks maybe automatically interconnected, means responsive tothe ini-r tiatioii of a vcall on one'yoi :said telephone y myfname this 2nd day of November,A. D.y

lines of a pair for connecting said pair of telephone lines to a` pair of idle trunks,a

bridge circuit, non-numerical switching controlledfover the calling line vfor connect-k ing thecalledtelephone line to an idle trunk,

means for interconnecting said last menktioned trunkand said bridge circuit.

times, one ot saidI sets of contacts being 18. In an automatic telephone system, a

Vplurality of telephone lines, a plurality of link circuits, non-numerical switching means including kbars f extending at substantially right angles to each other lfor extending telephone lines to idle linkcircuits, the numberk of saidvbars being. greater tliaii' the number ot said link circuits, aV bridge circuit, nonnumerical switching means for extending ka selected link circuit to an idle bridge circuit,

means kcontrolled over the calling telephone liney for causing said first mentioned switchrving. means to extend the wanted telephone line through a second link circuit to said bridge cir'cuit. n

19. In an automatic telephone system, a

plurality of telephone lines, a plurality ot ylinkk circuits, a cross-bar switch, contacts ot said telephone lines and contacts of said link n circuitsy in saidcross-bar switch, Ymeans n, operative on lthe initiation of a call on one `ot' sai'dtelephoneflines for causing contacts of said'plurality ottelephone lines to engage contactsoit a plurality of said link circuits whereby each oneof said plurality otlink circuits is 'selected by a .different one ot said Vtelephoner lines, and means including only i non-numerical switches and link circuits for extending the link,k circuit selected by the calling telephoneline to a wanted telephone line. n y y 20. In i' an automatic telephone system, a

plurality of` telephone lines arranged in pairs, a plurality oflink circuits alsoariaiigedfin pairs, fa cross-bar switch, contacts kfor eac-hpair of telephone lines and conand means including only knonnumerical I switches yand trunk ycircuits for extending the link circuit connectedto the calling tel-ephone line tothe vwanted telephone line.

`In witness whereof, l hereunto subscribe i i winiinnn T. POWELL. f 

